1. Field of the Invention
The invention relates to a teat cup assembly for application with a milking machine, said assembly comprising: a teat receiving head, a teat lining of flexible material connected with it, a limiter mounted over a part of the length of the teat lining, and an outer sleeve mounted at distance around said teat lining and being connected to the teat receiving head and at a distance to the teat lining, said outer sleeve being provided with a connection for generating a vacuum in the space between said teat lining and the outer sleeve.
2. Description of Related Art
Such a teat cup assembly is known from U.S. Pat. No. 4,269,143. In this known assembly, the limiter mounted on the teat lining is a sleeve slid onto the lining, said sleeve being made of an elastic material, just like the lining itself. Thus the limiter is able to move slightly in relation to the lining. The sleeve will not prevent the diameter of the teat lining from being larger during the section stroke than during the rest stroke. Only at the lower end of the limiter, the lining is provided with a protruding edge so that the limiter will not be able to slide away across the lining, to wit in the direction away from the receiving head. This will result in the fact, that a teat in the teat lining will be additionally loaded by creep of the teat lining. As a consequence, oedema could arise at the teat-udder junction.
Furthermore, the teat will get farther into the lining and will thus become additionally loaded during the rest stroke, since the circumference of the teat is larger than the inner circumference of the teat lining.
Further, U.S. Pat. No. 5,482,004 can be referred to, which shows a teat lining being provided with a reinforcement in the form of a rib extending helically around it, or ribs extending all round and spaced apart at some distance. Thus, enlargement of the teat lining diameter can hardly be prevented, whereas the effect of the ribs will be less great in the place between the ribs.
U.S. Pat. No. 2,164,706 discloses a teat cup assembly with a reinforcement in the form of a cotton cord which is mounted on the teat lining. Said cord is embedded in the material of the teat lining and is helically wound. The cord starts at some distance from the receiving head and is not suitable for preventing movement of the teat lining in longitudinal direction. Further, with this known assembly, the teat lining across the lower part thereof is completely in abutment with the outer sleeve and will not be slightly depressed on removing the underpressure in the space between it and the outer sleeve. As a result, its action will be completely different than that of the teat cup assembly according to the present invention.